New industry Technology regarding to Bussmann fuse, ABB breakers, Amphenol connectors, HPS transformers, etc.
We receive a customer complaint on the KLDR fuse when they have an incoming inspection. The PN: KLDR004 fuse cold resistance cannot meet the nominal data: 0.118 Ohm. The actual resistance is bigger than 0.9 Ohm.
Following is Bussmann FNQ and Littelfuse KLDR fuse manufacturer standard:
FNQ-R-1-1/2 = .5700 - .7490 Ohms
FNQ-R-5-6/10 = .0530 - .0590 Ohms
FNQ-R-1/2 = 5.220 – 7.400 Ohms.
KLDR.500 = 4-10 Ohms
KLDR 1-1/2= 0.898 - 1.2 Ohms
KLDR 008= 0.026 - 0.9 Ohms
Base on the testing result, the Customer change the KLDR fuse to FNQ.
When we select the time delay fuse to a EV charger customer.
Proposal PN1: Littelfuse, KLDR004
Proposal PN2: Bussmann,FNQ-R-4
Proposal PN3: Mersen,ATQR4
Applications: • Branch circuits • Line protection • Small control transformers • Industrial control
What are the factors we need to consider when choose fuse and fuse cross reference?
Suppose the system current is around 2.5~3A, Normally we will consider at least 1.6 times of system current in standard circuit( No big starting current)
So to choose 4A, these 3 time delay fuse models are all OK .
Littelfuse, KLDR004 | Bussmann,FNQ-R-4 | Mersen,ATQR4 |
Melt at 20S when input current is 10A | Melt at 11S when input current is 10A | Melt at 16S when input current is 10A |
Littelfuse, KLDR004 | Bussmann,FNQ-R-4 | Mersen,ATQR4 |
Fuse normal working tempeture: -20C ~40C. If your system tempeture is not in this range, you will need to consider to increase or decrease fuse current to meet the surrounding.
Littelfuse, KLDR004 | Bussmann,FNQ-R-4 | Mersen,ATQR4 |
Melt at 0.07S when input current is 40A | Melt at 0.3S when input current is 40A | Melt at 1.7S when input current is 40A |
Select time delay fuse is depends on system current, Peak let-through current, 2.5In , Teampeture etc factors, Also the mechanical design( Space, Bus-bar design), together with fuse price, leadtime, multiple factors you need to consider when design a proper fuse.
Bussmann catalog PN | Littelfuse cross reference PN | Fuse description |
FNQ-R-1 | KLDR001 | CLASS CC TIME DELAY 1A |
FNQ-R-1-1-2 | KLDR01.5 | 600VAC, 1.5A, CLASS CC TIME DELAY fuse |
FNQ-R-1-1-4 | KLDR1.25 | 1.25AMP fuse, CLASS CC TIME DELAY, 600VAC |
FNQ-R-1-1-8 | KLDR1.12 | TIME DELAY fuse, CLASS CC , 600VAC, 1.12A |
FNQ-R-1-2 | KLDR.500 | CLASS CC fuse, 0.5A, TIME DELAY |
FNQ-R-1-3-10 | KLDR01.3 | 1.3A, current limiting fuse, CLASS CC, TIME DELAY |
FNQ-R-1-4 | KLDR.250 | 0.25A, 600VAC, UL approval, CLASS CC, TIME DELAY fuse |
FNQ-R-1-4-10 | KLDR01.4 | TIME DELAY, CLASS CC, UL248-4 fuse, 1.4A |
FNQ-R-1-6-10 | KLDR01.6 | 600VAC, 1.6A, CLASS CC fuse, TIME DELAY |
FNQ-R-1-8-10 | KLDR01.8 | TIME DELAY, CLASS CC fuse, 1.8A |
FNQ-R-10 | KLDR010 | 10A, Transformer protection fuse, CLASS CC, TIME DELAY |
FNQ-R-12 | KLDR012 | REJECTION FUSE,CLASS CC, TIME DELAY, 12A |
FNQ-R-15 | KLDR015 | 15A, 600VAC, CLASS CC TIME DELAY REJECTION FUSE |
FNQ-R-17-1-2 | KLDR017.5 | 17.5A, UL, CSA, CE fuse, CLASS CC TIME DELAY |
FNQ-R-2 | KLDR002 | Current limiting fuse, 2A, TIME DELAY, CLASS CC |
FNQ-R-2-1-2 | KLDR02.5 | 300VDC, 600VAC, 2.5A, CLASS CC fuse |
FNQ-R-2-1-4 | KLDR2.25 | TIME DELAY,CLASS CC fuse, 2.25A, 300VDC |
FNQ-R-2-8-10 | KLDR02.8 | 2.8A, 300VDC, current limiting fuse,TIME DELAY |
FNQ-R-20 | KLDR020 | REJECTION FUSE, 20A, 300VDC, CLASS CC, TIME DELAY |
FNQ-R-25 | KLDR025 | CLASS CC, 20A, 600VAC, TIME DELAY, REJECTION FUSE |
FNQ-R-3 | KLDR003 | FUSE 3 A 600VAC, current limiting |
FNQ-R-3-1-2 | KLDR03.5 | 3.5A, UL248 fuse, 300VDC, CLASS CC TIME DELAY |
FNQ-R-3-10 | KLDR.300 | 0.3A fuse, transformer protection, CLASS CC, TIME DELAY |
FNQ-R-3-2-10 | KLDR03.2 | TIME DELAY,3.2A, 600VAC, CLASS CC fuse |
FNQ-R-3-4 | KLDR.750 | Fuse ratings: 0.75A, 300VDC, 600VAC, CLASS CC fuse |
FNQ-R-30 | KLDR030 | 10x38mm limitron fuse, 30A, CLASS CC TIME DELAY REJECTION FUSE |
FNQ-R-4 | KLDR004 | 4A, 600VAC, limitron fuse, TIME DELAY,CLASS CC |
FNQ-R-4-1-2 | KLDR4.25 | 300VDC, 4.25A, TIME DELAY,CLASS CC fuse |
FNQ-R-4-10 | KLDR.400 | CLASS CC, 0.4A, 600VAC, TIME DELAY fuse |
FNQ-R-5 | KLDR005 | 5A, industrial fuse, NEC , CLASS CC fuse |
FNQ-R-5-6-10 | KLDR05.6 | CLASS CC, 5.6A, commercial fuse |
FNQ-R-6 | KLDR006 | TIME DELAY, 6A, 300VDC, industrial transformer protection fuse |
FNQ-R-6-1-4 | KLDR6.25 | CLASS CC, 6.25A, 600VAC, NEC/UL/CSA/IEC fuse |
FNQ-R-6-10 | KLDR.600 | 0.6A, 300VDC, TIME DELAY fuse |
FNQ-R-7 | KLDR07 | 600VAC, 7A, CLASS CC, TIME DELAY fuse |
FNQ-R-7-1-2 | KLDR07.5 | 7.5A, TIME DELAY fuse |
FNQ-R-8 | KLDR008 | CLASS CC,10 X 38mm, 8A 600V AC fuse |
FNQ-R-8-10 | KLDR.800 | 300VDC/600VAC, 0.8A, CLASS CC fuse |
FNQ-R-9 | KLDR009 | CLASS CC, TIME DELAY, commercial fuse, 9A, 600VAC |
From the fuse size, we cannot recgonize the fuse quality. For fuse, the most improtant factor is resistance.
As we know, fuse element is made from silver belt. the silver belt purity is the heart for a fuse, especially high speed fuse; If fuse resistance is higher, it means that the fuse element silver purity is lower, Then the connecting performance will be impacted. The tempeture rise will be higher when operation. The fuse may will melt ahead or not melt timely instead.
If the fuse cannot melt in the right time, it cannot protect the circuit and devices accrodingly.
That's why the resistance is so important.
You can find fuse cross reference on Eaton, Littelfuse, Mersen. Engineers have professionally compare the performance.
No matter you are using time delay fuse or high speed fuse in current device, you will need to double check the fuse speed base on your application. Because you cannot test fuse speed in incoming inspection, fuse speed is a distructive experiment which only can be measured in fuse manufacturers side.
Maximum available fault current, Pulses, Surge Currents, Inrush Currents, Start-up Currents, and Circuit Transients
Such as UL, CSA, VDE, METI, MITI or Military
If you plan to use the alternate part in long term, suggest to test the fuse interchange part samples in your device; The fuse size, performance can be measured during single testing and system testing. Especially the tempeture rise, resistance etc electric performance.
This Chart is a Fuse block and holder cross reference for Class J, Class L, Class H, Class K, Class CC, 10*38mm Fuse.
Littelfuse | Bussmann | Mersen | Compatiable Fuse Link | Bussmann Fuse Holder Picture |
LFJ60030(X)/(X)ID | JM60030-(X)CR | 61006SJ,61008SJ | Class J Fuse | |
LFJ60060(X)/(X)ID | JM60060-(X)CR | |||
LFJ60100(X)/(X)ID | JM60100-(X)CR*** | |||
LFJ60200(X)/(X)ID | JM60200-(X)CR*** | |||
LFJ60400(X)/(X)ID | JM60400-(X)CR*** | |||
LFJ60600(X)/(X)ID | JM60600-(X)CR*** | |||
LFR25030(X)/(X)ID | RM25030-(X)CR | 22001R,22003R | Class R Fuse | |
LFR25060(X)/(X)ID | RM25060-(X)CR | |||
LFR25100(X)/(X)ID | RM25100-(X)CR*** | |||
LFR25200(X)/(X)ID | RM25200-(X)CR*** | |||
LFR25400(X)/(X)ID | RM25400-(X)CR*** | |||
LFR25600(X)/(X)ID | RM25600-(X)CR*** | |||
LFR60030(X)/(X)ID | RM60030-(X)CR | |||
LFR60060(X)/(X)ID | RM60060-(X)CR | |||
LFR60100(X)/(X)ID | RM60100-(X)CR*** | |||
LFR60200(X)/(X)ID | RM60200-(X)CR*** | |||
LFR60400(X)/(X)ID | RM60400-(X)CR*** | |||
LFR60600(X)/(X)ID | RM60600-(X)CR*** | |||
LFH25030(X)/(X)ID | HM25030-(X)CR | 22001,22003 | ||
LFH25060(X)/(X)ID | HM25060-(X)CR | |||
LFH25100(X)/(X)ID | HM25100-(X)CR*** | |||
LFH25200(X)/(X)ID | HM25200-(X)CR*** | |||
LFH25400(X)/(X)ID | HM25400-(X)CR*** | |||
LFH25600(X)/(X)ID | HM25600-(X)CR*** | |||
LFH60030(X)/(X)ID | HM60030-(X)CR | |||
LFH60060(X)/(X)ID | HM60060-(X)CR | |||
LFH60100(X)/(X)ID | HM60100-(X)CR*** | |||
LFH60200(X)/(X)ID | HM60200-(X)CR*** | |||
LFH60400(X)/(X)ID | HM60400-(X)CR*** | |||
LFH60600(X)/(X)ID | HM60600-(X)CR*** | |||
LFPSJ30(X)/(X)ID | CH30J(X)/(X)I | US3J(X)US3J(X)I | Class J Fuse | |
LFPSJ60(X)/(X)ID | CH60J(X)/(X)I | US6J(X)US6J(X)I | Class J Fuse | |
LPHV | CHPV | USM1HEL | PV-(XX)A10F | |
LPSC00(X)/(X)ID | CHCC(X)DU/(X)DIU | USCC(X)/USCC(X)I | KTK-R, LP-CC and FNQ-R Class CC fuse | |
LPSM00(X)/(X)ID | CHM(X)DU/CHM(X)DIU | USM(X)/USM(X)I | BAF,BAN,FNM, |
New industry Technology regarding to Bussmann fuse, ABB breakers, Amphenol connectors, HPS transformers, etc.